Track local dirty state in StateManagerGL. Make the state setting functions of StateManagerGL public. BUG=angleproject:1113 Change-Id: Ic435c06ece24064a2f2403119fa30309aba37608 Reviewed-on: https://chromium-review.googlesource.com/295240 Reviewed-by: Corentin Wallez <cwallez@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>